Biological sciences

Phenotypic plasticity of crown structure and function

Article Abstract:

In the poplar tree, Populus, the whole-tree leaf area derives from three shoot types. In a warmer, sunnier, environment with more water, trees 2 years old produced more, larger, wider leaves and more and longer branches. In a cooler, cloudier coastal area, the leaves were less large, less wide and branches fewer and shorter with sylleptic branches phenotypically more plastic than other parts of the crown. Proleptic traits better predicted stem height and basal area growth than did sylleptic traits, in either environment.

Phenotypic plasticity in the expression of self-incompatibility in Campanula rapunculoides

Article Abstract:

Quantitative genetics has examined the breakdown of self-incompatibility (SI) in the perennial bellflower Campanula rapunculoides. When cloned, the genotype produced few developing fruits on young flowers while old flowers showed weaker SI. The stigmatic curling that indicates age does not influence SI expression. The occurrence of SI may be produced through genotype-by-environment interactions.